I'm trying not to play the "everyone else should do like America because we've already been through anything they experience" game, but this really does look like the Rodney King riots all over again, and cops didn't end that, the National Guard did, in tanks and armed with automatic rifles. The cops were overwhelmed, and a lasting complaint of business owners (some of whom defended their livelihoods with their own automatic rifles) was that they repeatedly called police who never showed. In the infamous case of Reginald Denny, who was pulled from his vehicle and nearly beaten to death by rioters, cops had been ordered out of the area because it was unsafe. I don't know the law in Britain, except that it can be very different than in the US, but in Americas it's common knowledge that, during a riot, looters can and will be shot on sight. Send in the army and let them deal with this, because the police don't have the manpower or equipment to deal with a mass uprising.